nbd/server: Favor [u]int64_t over off_t
Although our compile-time environment is set up so that we always
support long files with 64-bit off_t, we have no guarantee whether
off_t is the same type as int64_t. This requires casts when
printing values, and prevents us from directly using qemu_strtoi64()
(which will be done in the next patch). Let's just flip to uint64_t
where possible, and stick to int64_t for detecting failure of
blk_getlength(); we also keep the assertions added in the previous
patch that the resulting values fit in 63 bits. The overflow check
in nbd_co_receive_request() was already sane (request->from is
validated to fit in 63 bits, and request->len is 32 bits, so the
addition can't overflow 64 bits), but rewrite it in a form easier
to recognize as a typical overflow check.
Rename the variable 'description' to keep line lengths reasonable.
Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190117193658.16413-7-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
diff --git a/include/block/nbd.h b/include/block/nbd.h
index 1971b55..24be957 100644
--- a/include/block/nbd.h
+++ b/include/block/nbd.h
@@ -294,8 +294,8 @@
typedef struct NBDExport NBDExport;
typedef struct NBDClient NBDClient;
-NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, off_t size,
- const char *name, const char *description,
+NBDExport *nbd_export_new(BlockDriverState *bs, uint64_t dev_offset,
+ uint64_t size, const char *name, const char *desc,
const char *bitmap, uint16_t nbdflags,
void (*close)(NBDExport *), bool writethrough,
BlockBackend *on_eject_blk, Error **errp);
diff --git a/nbd/server.c b/nbd/server.c
index 51ee809..cb0d563 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -77,8 +77,8 @@
BlockBackend *blk;
char *name;
char *description;
- off_t dev_offset;
- off_t size;
+ uint64_t dev_offset;
+ uint64_t size;
uint16_t nbdflags;
QTAILQ_HEAD(, NBDClient) clients;
QTAILQ_ENTRY(NBDExport) next;
@@ -1455,8 +1455,8 @@
nbd_export_close(exp);
}
-NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, off_t size,
- const char *name, const char *description,
+NBDExport *nbd_export_new(BlockDriverState *bs, uint64_t dev_offset,
+ uint64_t size, const char *name, const char *desc,
const char *bitmap, uint16_t nbdflags,
void (*close)(NBDExport *), bool writethrough,
BlockBackend *on_eject_blk, Error **errp)
@@ -1495,12 +1495,12 @@
exp->refcount = 1;
QTAILQ_INIT(&exp->clients);
exp->blk = blk;
- assert(dev_offset >= 0 && dev_offset <= INT64_MAX);
+ assert(dev_offset <= INT64_MAX);
exp->dev_offset = dev_offset;
exp->name = g_strdup(name);
- exp->description = g_strdup(description);
+ exp->description = g_strdup(desc);
exp->nbdflags = nbdflags;
- assert(size >= 0 && size <= INT64_MAX - dev_offset);
+ assert(size <= INT64_MAX - dev_offset);
exp->size = QEMU_ALIGN_DOWN(size, BDRV_SECTOR_SIZE);
if (bitmap) {
@@ -2130,10 +2130,10 @@
return -EROFS;
}
if (request->from > client->exp->size ||
- request->from + request->len > client->exp->size) {
+ request->len > client->exp->size - request->from) {
error_setg(errp, "operation past EOF; From: %" PRIu64 ", Len: %" PRIu32
", Size: %" PRIu64, request->from, request->len,
- (uint64_t)client->exp->size);
+ client->exp->size);
return (request->type == NBD_CMD_WRITE ||
request->type == NBD_CMD_WRITE_ZEROES) ? -ENOSPC : -EINVAL;
}
diff --git a/qemu-nbd.c b/qemu-nbd.c
index 5c90c5e..598caa6 100644
--- a/qemu-nbd.c
+++ b/qemu-nbd.c
@@ -176,7 +176,7 @@
}
static int find_partition(BlockBackend *blk, int partition,
- off_t *offset, off_t *size)
+ uint64_t *offset, uint64_t *size)
{
struct partition_record mbr[4];
uint8_t data[MBR_SIZE];
@@ -500,14 +500,14 @@
{
BlockBackend *blk;
BlockDriverState *bs;
- off_t dev_offset = 0;
+ uint64_t dev_offset = 0;
uint16_t nbdflags = 0;
bool disconnect = false;
const char *bindto = NULL;
const char *port = NULL;
char *sockpath = NULL;
char *device = NULL;
- off_t fd_size;
+ int64_t fd_size;
QemuOpts *sn_opts = NULL;
const char *sn_id_or_name = NULL;
const char *sopt = "hVb:o:p:rsnP:c:dvk:e:f:tl:x:T:D:B:";
@@ -665,10 +665,6 @@
error_report("Invalid offset `%s'", optarg);
exit(EXIT_FAILURE);
}
- if (dev_offset < 0) {
- error_report("Offset must be positive `%s'", optarg);
- exit(EXIT_FAILURE);
- }
break;
case 'l':
if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
@@ -1005,15 +1001,14 @@
}
if (dev_offset >= fd_size) {
- error_report("Offset (%lld) has to be smaller than the image size "
- "(%lld)",
- (long long int)dev_offset, (long long int)fd_size);
+ error_report("Offset (%" PRIu64 ") has to be smaller than the image "
+ "size (%" PRId64 ")", dev_offset, fd_size);
exit(EXIT_FAILURE);
}
fd_size -= dev_offset;
if (partition != -1) {
- off_t limit;
+ uint64_t limit;
if (dev_offset) {
error_report("Cannot request partition and offset together");
@@ -1027,15 +1022,13 @@
}
/*
* MBR partition limits are (32-bit << 9); this assert lets
- * the compiler know that we have two positive values that
- * can't overflow 64 bits.
+ * the compiler know that we can't overflow 64 bits.
*/
- assert(dev_offset >= 0 && dev_offset + limit >= dev_offset);
+ assert(dev_offset + limit >= dev_offset);
if (dev_offset + limit > fd_size) {
- error_report("Discovered partition %d at offset %lld size %lld, "
- "but size exceeds file length %lld", partition,
- (long long int) dev_offset, (long long int) limit,
- (long long int) fd_size);
+ error_report("Discovered partition %d at offset %" PRIu64
+ " size %" PRIu64 ", but size exceeds file length %"
+ PRId64, partition, dev_offset, limit, fd_size);
exit(EXIT_FAILURE);
}
fd_size = limit;
